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    <title>Document</title>
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    <script>
        const SCHOOL = '尚硅谷'
        // 1.一定要赋初始值
        const A //报错

        // 2.一般常量用大写(潜规则)

        // 3.常量的值不能修改
        SCHOOL = '11111'

        // 4.块级作用域
        {
            const PLAYER = 'uzi'
        }
        console.log(PLAYER) //报错找不到

        // 5.对于数组和对象的元素修改,不算做对常量的修改,不会报错
        const TEAM = ['uzi', 'mlxg', 'ming', 'letme']
        TEAM.push('meiko')
    </script>
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